Britain's Allan McNish qualified in fourth position before the penultimate round of the World Endurance Championship (WEC) in Shanghai on Friday and, although the driver was disappointed, he knows it is the exact position he must claim in the race in order to secure the drivers' championship in China on Saturday.

If he does so, he will be the first British sportscar world champion since Derek Warwick won the title in 1992. Pole was taken by the No7 Toyota of Alex Wurz and Nicolas Lapierre, who set the fastest four-lap average time of 1min 48.013sec.

The No2 Audi of McNish, Tom Kristensen and Loïc Duval had set the quickest time in first practice in the morning and the sister No1 car of André Lotterer, Benoît Tréluyer and Marcel Fässler dominated the second session, although their fastest time was ultimately disallowed. But when it counted neither could match the time set by the No7 car at this truncated race weekend that is taking place over two days.

It is only the second time the Toyota drivers and team have been on pole this season, having claimed the top spot at the season opener at Silverstone, although they have form at the Shanghai International Circuit, with Wurz and Lapierre taking pole and winning here last year.

They were quicker than Fässler and Tréluyer by only eight hundredths of a second, with Tréluyer heading out at the end in an attempt to bag pole that was not quite enough. The No1 Audi, driven by last year's championship winners, knew they had to go all out since they must win here and hope the No2 car finishes outside the top four to have any chance of taking the championship to the final race in Bahrain.

The sister Toyota No8, qualified by Stéphane Sarrazin and Sébastien Buemi, who will race alongside Anthony David, was in third place, 0.6sec back.

The McNish car has won three races (including the Le Mans 24 Hours) and finished second in three others this season, which has placed the team in such a dominant position going into the seventh round. But the British driver is taking nothing for granted.

"It was a tough day and we have a fight on our hands," said McNish who finished second at Shanghai last year.

"We had two practice sessions and then qualifying all in close succession during the course of the day. In second practice our car didn't run at full capacity and that possibly affected our performance in qualifying."

The Shanghai International Circuit is hard on tyres on the prototype cars and degradation is likely to be high, suggesting that strategy as well as raw pace may be key to his attempt to become world champion on Saturday.